I've been building a small web app that complements my employer's industry without really being what I was hired for...so I was torn about whether he would seek

I've been building a small web app that complements my employer's industry without really being what I was hired for...so I was torn about whether he would seek to take possession. I ultimately showed the app to my employer but not before having spent a weekend in the mountains really reflecting on what I'd want if it came down to negotiating with him. And first and foremost I wanted creative control. If he had decided that he was going to commandeer it (which I presumed would be his legal right, and I didn't want to get into a legal fight), then I was going to fight to at least manage the project in house. We're not a tech company, and he is willing to let me build and manage it on my own...but it was very helpful for me to see that what I wanted was control.